US10357361B2 - Heart valve pinch devices and delivery systems - Google Patents

Abstract

Pinch devices and access systems that can be used to secure a prosthetic heart valve to a heart valve annulus and to treat valvular insufficiency. A pinch device can be a separate expandable element from the prosthetic heart valve that is first advanced to the annulus and deployed, after which an expandable prosthetic heart valve can be advanced to within the annulus and deployed. The two elements can clamp/pinch the heart valve leaflets to hold the prosthetic heart valve in place. The pinch device can have a flexible, expandable annular frame. A combined delivery system can deliver the pinch device and prosthetic heart valve with just a single access point and aid more accurate coaxial deployment. The pinch device can be mounted near distal end of an access sheath, and a catheter for delivering the prosthetic heart valve can be passed through a lumen of the same access sheath.

Description

RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 to U.S. Provisional Application No. 62/395,283, filed Sep. 15, 2016, which is incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to heart valve repair, including heart valve repair using a heart valve pinch device and corresponding delivery system and method.

BACKGROUND OF THE INVENTION

The heart is a hollow muscular organ having four pumping chambers separated by four heart valves: aortic, mitral (or bicuspid), tricuspid, and pulmonary. Heart valves are comprised of a dense fibrous ring known as the annulus, and leaflets or cusps attached to the annulus.

Prosthetic heart valves can be used to treat cardiac valvular disorders. The native heart valves (such as the aortic, pulmonary, tricuspid, and mitral valves) serve critical functions in assuring the forward flow of an adequate supply of blood through the cardiovascular system. These heart valves can be rendered less effective by congenital, inflammatory, or infectious conditions. Such conditions can eventually lead to serious cardiovascular compromise or death. It is possible to surgically repair or replace the valve during open heart surgery, where a prosthetic valve is sutured in place, but such surgeries are time-consuming, dangerous and prone to complication.

Transvascular and transapical techniques can be used for introducing and implanting a prosthetic heart valve using a flexible catheter in a manner that is less invasive than open heart surgery. In these techniques, a prosthetic valve can be mounted in a crimped state on the end portion of a flexible catheter and advanced through a blood vessel of the patient until the valve reaches the implantation site. The valve at the catheter tip can then be expanded to its functional size at the site of the defective native valve, such as by inflating a balloon on which the valve is mounted. Alternatively, the valve can have a resilient, self-expanding stent or frame that expands the valve to its functional size when it is advanced from a delivery sheath at the distal end of the catheter. These are sutureless techniques which greatly reduces the procedure time.

Balloon-expandable valves can be used for treating heart valve stenosis, a condition in which the leaflets of a valve (e.g., an aortic valve) become hardened with calcium. The hardened leaflets provide a good support structure on which the valve can be anchored within the valve annulus. Further, the catheter balloon can apply sufficient expanding force to anchor the frame of the prosthetic valve to the surrounding calcified tissue. There are several heart conditions, however, that do not involve hardened valve leaflets but which are still desirably treated by valve replacement. For example, aortic insufficiency (or aortic regurgitation) occurs when an aortic valve does not close properly, allowing blood to flow back into the left ventricle. One cause for aortic insufficiency is a dilated aortic annulus, which prevents the aortic valve from closing tightly. In such cases, the leaflets are usually too soft to provide sufficient support for a balloon-expandable prosthetic valve. Additionally, the diameter of the aortic annulus may continue to vary over time, making it dangerous to install a prosthetic valve that is not reliably secured in the valve annulus. Similar problems can occur with other heart valves as well. For example, mitral insufficiency (or mitral regurgitation) involves these same conditions but affects the mitral valve.

Self-expanding prosthetic valves can suffer from other problems. For example, if a self-expanding prosthetic valve is placed within the patient's defective heart valve (e.g., the aorta or mitral valve), it could continues to exert an outward force on the valve annulus. This continuous outward pressure could cause the valve annulus to dilate further, exacerbating the condition the valve was intended to treat. Additionally, when implanting a self-expanding valve, the outward biasing force of the valve's frame could cause the valve to be ejected very quickly from the distal end of a delivery sheath. This makes delivery of the valve very difficult and dangerous to the patient.

The size of the prosthetic valve to be implanted into a patient can also be problematic when treating aortic or mitral insufficiency. Specifically, the size of a prosthetic valve used to treat aortic or mitral insufficiency would generally need to be larger than a prosthetic valve used to treat aortic or mitral stenosis. This larger valve size can make the delivery procedure much more difficult and dangerous to the patient.

Another potential issue with sutureless valves is valve migration. For example, when an aortic prosthetic valve is implanted, 100-200 mmHg pressure loads on the aortic valve immediately. The pressure times the valve surface area produces a substantial load force on the prosthetic valve and could cause valve migration towards the aortic arch. Another potential cause of valve migration is a tilted valve landing. When tilted, the prosthetic valve will have a larger surface area facing the blood flow, which could push the prosthetic valve into the aorta.

Treatment of the mitral valve can present additional challenges, and methods and an apparatus appropriate for the aortic valve may not be well suited for use with the mitral valve. For instance, the mitral valve includes clusters of chordae tendineae extending from the valve leaflets to the walls of the ventricle that may interfere with placement of the prosthesis. The shape of the mitral valve, rather than being circular and uniform like the aortic valve, can be an oval or kidney-like shape that may not be well suited for supporting conventional stents of cylindrical configuration. Further, whereas the aortic valve annulus is often entirely surrounded by muscular tissue, the mitral valve annulus may be bounded by muscular tissue on the outer (posterior) wall only. The anterior side of the mitral valve annulus is bounded by a thin vessel wall adjacent the left ventricular outflow tract (“LVOT”), which must remain open to allow blood to pass into the aorta. As a result, the stent-type fixation may not be suitable for the mitral valve because the anterior side of the native valve has insufficient radial strength and can distort, risking occlusion of the left ventricular outflow tract. Moreover, mitral valve disease often is accompanied by (or caused by) gradual enlargement of the native annulus and/or the left ventricle. Thus, treatment approaches which rely upon radial engagement with or outward compression against the native annulus are subject to failure as the size and shape of the annulus changes.

There is a need for improved methods, systems, and apparatus for delivering expandable prosthetic heart valves (e.g., balloon-expandable or self-expandable prosthetic valves). Embodiments of the methods, systems, apparatus, devices, components, etc. disclosed herein can be used to replace native heart valves even when they do not have calcified leaflets (e.g., aortic valves suffering from aortic insufficiency).

SUMMARY OF THE INVENTION

Among other things, the present application discloses embodiments of a pinch device used to secure a prosthetic heart valve to a heart valve annulus. The pinch device can also be termed a grip, a dock, a constrictor, etc., and can comprise a separate expandable element that is first advanced to the heart valve annulus and deployed, after which an expandable heart valve is advanced to the annulus and deployed. The combination of the two elements applies a clamping/pinching force to the heart valve leaflets which holds the prosthetic heart valve in place.

The pinch device embodiments herein can be used with a number of expandable heart valves having either self- or mechanically- or balloon-expandable support frames. The system formed by the prosthetic heart valve and pinch device may be implanted at any of the native heart valves, for example, the aortic and mitral heart valves.

The pinch device can be a flexible, self-expandable annular stent-like frame. The frame can have a continuous undulating shape with peaks and valleys. While various numbers of peaks and valleys can be used, in one embodiment, there are at least three and up to six peaks and three valleys. The pinch device can be made of a super-elastic metallic alloy such as Nitinol, or a similar expedient.

A deployment or delivery system can include a tubular access/delivery sheath. The access/delivery sheath can have a pinch device (e.g., any of the pinch devices described in this disclosure) mounted near the distal end thereof. The access/delivery sheath can also include a lumen through which a catheter for delivering the prosthetic heart valve is passable. This combined delivery system for the pinch device and prosthetic heart valve requires just a single access point, and the prosthetic heart valve remains coaxial to the pinch device for more precise deployment therein.

An exemplary prosthetic heart valve system or prosthetic heart valve and delivery system can comprise a variety of features and components. For example, the system can include an expandable prosthetic heart valve having a constricted diameter and an expanded diameter. The system can also include a delivery catheter having a distal end on or in which the heart valve is mounted. The system can also include a pinch device separate from the heart valve that has an expanded state defining an annular frame formed around a central axis. The frame can have peaks and valleys (e.g., 2-12 peaks and/or 2-12 valleys) extending in opposite axial directions around its periphery.

The pinch device can include a super-elastic inner body or frame. The body/frame can be fully or partially covered with a biocompatible fabric covering. The body/frame can have a plurality of buckles integrated with the inner body/frame, and the plurality of buckles can project from a proximal end (or distal end) with or without any fabric covering. The pinch device in its expanded state can be sized slightly smaller than the expanded diameter of the heart valve.

The system can include an access system, and the access system can have a proximal handle and a distal access sheath. The handle and sheath can define a common lumen sized for passage therethrough of the distal end of the delivery catheter with the heart valve in its constricted diameter thereon. The handle can include one or more hemostatic seals to prevent blood leakage proximally past the distal end of the delivery catheter during use, e.g., as the delivery catheter passes through the lumen of the handle and sheath. The access system can further include a plurality of deployment arms fixed or axially movable therein, and each deployment arm can be coupled to one of the buckles of the pinch device. The pinch device can be positioned in a constricted state within a distal end of the access sheath and can be located distal with respect to the distal end of the delivery catheter, such that the pinch device can be expelled from the access sheath and self-expand prior to the heart valve by distal advancement of the deployment arms and/or retraction of the sheath.

The distal access sheath can be sized and configured to be introduced into the heart and advanced so that the distal end thereof is adjacent a native heart valve, whereupon the pinch device can be expelled therefrom and positioned around native heart valve leaflets and the delivery catheter can be advanced to position the heart valve within the native heart valve leaflets such that expansion of the heart valve pinches the leaflets between the heart valve and pinch device.

Methods of using the various systems and/or devices herein and methods of treating native heart valves (e.g., valvular insufficiency) can include any of the steps described in this disclosure. For example, a beating heart method can include forming a single access point, for example through the mid-sternum area and into the left ventricle adjacent the apex of the heart. Alternatively, the single access point may be formed in the upper leg and into the femoral artery. After appropriate puncturing, widening/dilating, and sealing the access point, a tubular access sheath can be introduced and advanced into proximity with the native heart valve being replaced. For instance, the access sheath can be advanced into the left ventricle and through the aortic valve such that a distal end is positioned in the ascending aorta. A pinch device can then be expelled from the distal end of the access sheath and permitted to expand. Retraction of the access sheath can cause or permit the pinch device to seat against the aortic valve outside (e.g., partially or fully outside) of the aortic leaflets.

The pinch device can be desirably held by elongated arms (e.g., three elongated arms, 2-9 elongated arms, etc.) extending from the access sheath. The arms can be spaced apart (e.g., three arms spaced 120° apart, two arms spaced 180° apart, or in other spacing arrangements such that the arms can pass between native leaflets at commissures). In one embodiment, three arms can be spaced about 120° apart (e.g., ±5°) and can be configured to and/or positioned such that they pass between the aortic leaflets in the commissure regions. Consequently, the aortic valve can continue to function during the procedure.

A replacement prosthetic heart valve can then be advanced through the access sheath and within the aortic leaflets. The health care provider (e.g., doctor, surgeon, etc.) can expand the heart valve either by releasing it from a constraining sheath or by outward expansion with a balloon or mechanically, for example. Expansion of the heart valve traps aortic leaflets between it and the surrounding pinch device. The deployment arms can then be released from engagement with the pinch device, and the access sheath and delivery components removed from the body. A similar procedure can be performed to replace the mitral valve, and either procedure can be accomplished using different access points such as a percutaneous route through the femoral artery.

Methods, e.g., beating heart methods of delivering a prosthetic heart valve through a single access point, can comprise first providing or obtaining an access/delivery system including a proximal handle and a distal access sheath. The handle and sheath can define a common lumen. At the distal end of the access system and sheath can be provided a pinch device in a constricted state, wherein the pinch device has an expanded state defining an annular frame. The pinch device can be the same as or similar to other pinch devices described in this disclosure. The frame of the pinch device can be formed around a central axis having peaks and valleys (e.g., 2-12 peaks and 2-12 valleys) extending in opposite axial directions around its periphery. The pinch device can include a super-elastic inner body/frame, and can be covered (e.g., fully or partially) with a biocompatible fabric covering. The pinch device or inner body/frame can include a plurality of buckles integrated with the inner body/frame. The buckles can project from a proximal end with or without any fabric covering (e.g., the biocompatible fabric covering can extend over all or a portion of the buckles, or not extend to the buckles). The access system can further include a plurality of deployment arms fixed or axially movable therein. Each arm can be coupled to one of the buckles of the pinch device. The pinch device can be positioned in a constricted state within a distal end of the access sheath, and the pinch device can thus be expelled from the access sheath and self-expand by distal advancement of the deployment arms and/or retraction of the sheath.

The methods can further involve inserting a delivery catheter having an expandable prosthetic heart valve mounted on a distal end into the common lumen from the handle. The prosthetic heart valve can be the same as or similar to other prosthetic heart valves described in this disclosure. For example, the prosthetic heart valve can have a constricted diameter and an expanded diameter, and the delivery catheter and prosthetic heart valve in its constricted diameter can be sized to pass entirely through the common lumen and within the deployment arms. The expanded diameter of the prosthetic heart valve can be slightly larger than a diameter of the pinch device in its expanded state to improve retention.

While the heart is beating, an access incision can be formed to gain access to a heart chamber, and the access sheath can be advanced through the access incision until the distal end of the sheath is located adjacent or proximate a native heart valve annulus. The health care provider (e.g. doctor, physician, surgeon, etc.) can expel the pinch device from the access sheath, e.g., by distal advancement of the deployment arms and/or retraction of the sheath, such that the pinch device is unconstrained and self-expands to its expanded state. The health care provider can then position the expanded pinch device around native heart valve leaflets. The delivery catheter can be advanced though the access system to position the prosthetic heart valve within the native heart valve leaflets and within the pinch device. The prosthetic heart valve can be expanded to pinch the native heart valve leaflets between the prosthetic heart valve and pinch device, and the deployment arms can be decoupled from the buckles to release the pinch device.

An exemplary pinch device for securing a prosthetic heart valve to native heart valve leaflets, can comprise a device that has a constricted state and an expanded state defining an annular frame. The annular frame can be formed around a central axis and can have peaks and valleys extending in opposite axial directions around its periphery. The peaks of the pinch device can project in a distal direction and the valleys can project in a proximal direction. The pinch device can include a super-elastic inner body covered with a biocompatible fabric and the inner body can include a plurality of buckles with or without any fabric covering. The buckles can be located at terminal ends of three fingers extending in a proximal direction or distal direction from three of the peaks of the pinch device. The fingers and buckles can be distributed evenly or asymmetrically around a periphery of the pinch device. The pinch device can be sized slightly smaller than an expanded diameter of a heart valve, such that the pinch device can be expanded and positioned around native heart valve leaflets, and expansion of the heart valve within the leaflets pinches the leaflets between the heart valve and pinch device. The inner body can include circumferential struts connecting each two adjacent peaks and valleys. The struts can be a variety of shapes and sizes. In one embodiment, each strut is generally S-shaped, with two curvatures separated by a point of inflection. Each of the circumferential struts can terminate at its corresponding peak and valley in an asymptotic manner such that it is nearly aligned or parallel with the vertical Z-axis.

The various systems and devices described above can include features and components from other systems and devices described elsewhere herein and certain features/components described above can be omitted. Similarly methods described above can include additional steps described elsewhere herein and certain steps described above can be omitted.

Other features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of an exemplary fabric-covered pinch device (e.g., a grip, dock, constrictor, etc.) having three peaks and valleys around its circumference for use in heart valve placement procedures described herein, andFIG. 1B is a perspective view of an inner body of the pinch device without the fabric covering;

FIGS. 2A-2E are schematic sectional views of a native aortic valve showing sequential steps in transapical deployment of the exemplary pinch device and an expandable prosthetic heart valve therein during an aortic valve replacement procedure;

FIG. 3A is a perspective view of an exemplary pinch device having six peaks and valleys around its circumference for use in heart valve replacement procedures described herein, andFIG. 3B is an exemplary pinch device modified for another valve replacement procedure;

FIGS. 4A-4D are perspective views of an exemplary access/delivery system having a tubular access/delivery sheath for deploying the pinch devices described herein showing sequential steps in expulsion and release of an exemplary pinch device from the sheath;

FIGS. 5A and 5B are enlarged perspective views of an exemplary coupling arrangement between one of a plurality of deployment arms extending from the access sheath and an exemplary manipulation buckle extending proximally from the pinch device in both coupled and uncoupled configurations;

FIG. 6A is a broken vertical sectional view through the exemplary access/delivery system including the access/delivery sheath with an exemplary pinch device therein and a proximal handle;

FIG. 6B is a vertical sectional view through a distal end of the access sheath after expulsion of the pinch device therefrom but before decoupling of the deployment arms;

FIG. 6C is a vertical sectional view through the proximal handle of the access system in particular showing a number of exemplary hemostatic seals, andFIGS. 6D and 6E are enlarged views of portions thereof;

FIGS. 7A-7C are enlarged views of a proximal end of the access system handle showing operation of an arm decoupling assembly;

FIG. 8 is an exploded perspective view of the proximal end of the access system handle showing an inner face of an end cap thereof; and

FIGS. 9A and 9B are elevational views of the end cap inner face relative to a plurality of locking tabs in the handle in two different rotational orientations.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Disclosed herein are representative embodiments of a pinch device (sometimes referred to as a “grip,” “dock,” “constrictor,” etc.) that can be used to secure a prosthetic heart valve within a native heart valve. For illustrative purposes, embodiments of the pinch device are described as being used to secure an expandable heart valve such as a transcatheter heart valve (“THV”) in the aortic valve or the mitral valve of a heart. The annular pinch device surrounds native heart valve leaflets and the heart valve is expanded within the leaflets so as to “pinch” the leaflets therebetween. It should be understood that the disclosed pinch device and THV can be configured for use with any native heart valve. Also disclosed herein are exemplary methods and systems for deploying the pinch device and corresponding THV, e.g., in a coordinated manner using a single access point.

The pinch device is desirably used in connection with embodiments of a balloon-expandable THV such as the Edwards SAPIEN 3 Transcatheter Heart Valve made by Edwards Lifesciences of Irvine, Calif., or such as described in U.S. Pat. No. 6,730,118, which is hereby expressly incorporated herein by reference. However, these exemplary THVs should not be construed as limiting, and embodiments of the disclosed pinch device can be used to secure a wide variety of THVs delivered through a variety of mechanisms (e.g., self-expanding heart valves, mechanically-expandable heart valves, other balloon-expanding heart valves, combinations of these, and the like). The term, “expandable heart valves” is intended to encompass all such varieties.

FIG. 1A is a perspective view of an exemplary fabric-covered pinch device20 (grip, dock, constrictor, etc.), andFIG. 1B is a perspective view of aninner body22 of the pinch device without a fabric covering24. Thepinch device20 has a generally annular or toroidal body arranged around a vertical Z-axis26 and formed from a suitable super-elastic metal or alloy, such as Nitinol. Other shapes and/or materials are also possible. Optionally, spring steel, a cobalt-chrome alloy such as Elgiloy®, or other such elastic metals can be utilized with some modification to the delivery system. Desirably, the material from which thepinch device20 is fabricated allows it to be radially compressed to a reduced profile for delivery through the patient's vasculature and automatically expanded to its functional size and shape when deployed. With a supra-elastic material such as Nitinol the reduced radial profile can be very small, whereas with other materials which are not so flexible, thepinch device20 may only be partially constricted for delivery and then permitted to expand.

Although various numbers/arrangements of peaks and valleys are possible, the illustratedpinch device20 includes threepeaks30,32,34 evenly alternating with threevalleys40,42,44 around its circumference. More particularly, thepeaks30,32,34 are spaced 120° apart, each 60° separated fromadjacent valleys40,42,44. The peaks and valleys desirably lie in a tubular space such that thepeaks30,32,34 are positioned above thevalleys40,42,44 in the Z-direction. In some embodiments, thepeaks30,32,34 have greater radii than thevalleys40,42,44, or vice versa. For instance, in some embodiments, the projection of thepinch device20 onto an x-y plane forms a closed shape having a variable radius (e.g., a starfish shape).

In terms of orientation, the pinch devices herein can be delivered in a direction toward the target native heart valve with either the peaks or the valleys leading, which will determine the proximal and distal directions. That is, the leading end of an implant in a delivery procedure is termed the distal end, and vice versa. In the illustrated embodiment, thepeaks30,32,34 of thepinch device20 are on the leading end and thus form the distal end of the device, while thevalleys40,42,44 are on the trailing or proximal end. Furthermore, for the purpose of clarity and reference, the distal direction coincides with up along the Z-axis26 inFIGS. 1A and 1B, while the proximal direction coincides with down.

A plurality of struts can be used between adjacent peaks and/or valleys. For example, circumferential struts46,48 connect each twoadjacent peaks30,32,34 andvalleys40,42,44. More particularly, as viewed looking down along theaxis26, a firstcircumferential strut46 extends clockwise (CW) down from each one of thepeaks30,32,34 to each one of thevalleys40,42,44, and a secondcircumferential strut48 extends up from the valley CW to the next peak. The struts (e.g., circumferential struts46,48) can be configured in a variety of shapes and sizes, e.g., straight, curved, zig-zag, symmetrical, asymmetrical, etc. For example, inFIGS. 1A and 1B, thestruts46,48 are shown as being generally S-shaped, with two distinct curvatures separated by a point of inflection. Each of thestruts46,48 can terminate at its corresponding peak and valley in an asymptotic manner such that it is nearly aligned with the vertical Z-axis26. Looking at the firstcircumferential strut46 inFIGS. 1A and 1B extending between the peak34 and thevalley44, afirst segment50 initially extends downward in a nearly vertical direction and has a concave up curvature until a point ofinflection52 at a midpoint of the strut. From there, asecond segment54 is curved concave down until it is nearly vertical at thevalley44. When implanted, thestruts46,48 are in direct contact with the native heart valve leaflets, as will be explained, and this S-shaped configuration enhances their ability to pinch or clamp a wide area of the leaflet against the expandable heart valve that is positioned within the leaflets.

A plurality of buckles60 (e.g., 2, 3, 4, 5, 6, or more) can be integrated with theinner body22 to facilitate manipulation and deployment of thepinch device20. The term “integrated” in this regard means that thebuckles60 are either formed homogeneously with the rest of theinner body22 as a single piece, or that the buckles are secured to theinner body22 in a manner which enables manipulation of the buckles to manipulate the inner body. For example, thebuckles60 may be welded to theinner body22 after fabrication of both. Each buckle of the plurality ofbuckles60 can be positioned on an end of an extension (e.g., a finger, peak, etc.). In the illustrated embodiment, eachbuckle60 is positioned on the lower end of avertical finger62 projecting downward from each one of thepeaks30,32,34. As seen inFIG. 1A, each of thebuckles60 remains exposed by virtue of not being covered by thefabric24, but embodiments in which thebuckles60 are covered are also possible. Not covering thebuckles60 may help prevent interference of the fabric covering with the release/deployment arms that hold the pinch device during delivery.

The extensions (e.g., fingers, etc.) can have a variety of shapes and sizes. For example, inFIGS. 1A and 1B, the vertical height A as measured along the Z-axis26 between thepeaks30,32,34 andvalleys40,42,44 is shorter than the length B of eachfinger62 withbuckle60, such that thebuckles60 extend below thevalleys40,42,44. In one embodiment, the height A can be between 13-14 mm, preferably about 13.9 mm, and the length B of eachfinger62 withbuckle60 can be between 16-18 mm, and preferably about 17.0 mm. Each one of the illustrated buckles60 can have a substantially open square shape, although other configurations/shapes (e.g., circular, oval, rectangular, polygonal, etc.) are contemplated. Eachbuckle60 can have a height of about 2 mm, such that the height C of eachfinger62 is between about 14-16 mm, and preferably about 15.0 mm. A circumferential span between each twoadjacent peaks30,32,34 (or between each twoadjacent valleys40,42,44) can vary depending on the particular size of valve being implanted, for example between about 23-29 mm. In one embodiment, the circumferential span between each twoadjacent peaks30,32,34 is about 27.1 mm such that a diameter of theinner body22 when formed into a toroid is about 25.9 mm, which would be suitable for clamping around a heart valve that expands to 27 mm.

The size of thepinch device20 can vary from implementation to implementation. In particular embodiments, thepinch device20 can be sized such that the pinch device can be positioned within the aorta of a patient at a location adjacent to the aortic valve, circumscribing the aortic valve and its leaflets. In order to frictionally secure a prosthetic heart valve in its interior, thepinch device20 has an expanded diameter that is slightly smaller than the diameter of the prosthetic heart valve when fully expanded. In particular embodiments, for instance, the pinch device can have an inner or outer diameter between 10 and 50 mm (e.g., between 17 and 28 mm) and a height between 5 and 35 mm (e.g., between 8 and 18 mm). Furthermore, the thickness of the annular body of thepinch device20 may vary from embodiment to embodiment, but in certain embodiments is between 0.3 and 1.2 mm. Thepinch device20 can be formed by laser-cutting the shape from a tubular blank, resulting in square or rectangular cross-sectional struts. Subsequently, the struts may be further processed such as with electropolishing to reduce any sharp edges or corners. Other manufacturing and processing techniques are also possible.

As seen best inFIG. 1B, thepeaks30,32,34 andvalleys40,42,44 can have flat ends that are perpendicular to the Z-axis26. This feature facilitates laser fabrication of thepinch device20 by eliminating tight curvatures at these points. Furthermore, because thepeaks30,32,34 comprise the leading end during a transapical delivery, these flat ends help prevent puncture of anatomical structures in case of any contact therewith.

Delivery Method

FIGS. 2A-2E are schematic sectional views of a native aortic valve AV showing sequential steps in an exemplary deployment of anexemplary pinch device20 and an expandable prosthetic heart valve therein during a beating heart valve replacement procedure. As mentioned, the exemplary procedure is one which utilizes a transapical access route to replace a dysfunctional aortic valve. The presently disclosedpinch device20 and associated delivery system are designed for this access route and native valve replacement, but those of skill in art will understand that certain modifications will enable procedures utilizing alternative access routes and for replacing different native valves. For example, the same transapical access route may be used to replace a mitral valve MV, though the shape of thepinch device20 may be modified to negotiate the chordae tendineae below the mitral valve.

In any event, the exemplary procedure commences by introduction of an access ordelivery sheath100 of an access or delivery system into the left ventricle LV through anapical puncture102 and advancing adistal end104 of the sheath along a previously located/positionedguide wire106 into proximity with the aortic valve AV. Although, use of a guidewire is optional. As seen inFIG. 2A, thedistal end104 can be positioned slightly beyond the aortic valve leaflets AVL and into the ascending aorta AA. Positioning of thedistal end104 can be assisted by external visualization such as ultrasound and/or fluoroscopy and radiopaque markers in the distal end.

Because theapical puncture102 is properly sealed around the access/delivery sheath100, and due to other surgical precautions, the operation can be accomplished while the heart is beating. Although not shown, introduction of the access/delivery sheath100 to theapical puncture102 typically occurs via an intercostal incision, often termed a “mini-thoracotomy.” Local exposure of the exterior of the heart is then attained using subcutaneous incisions along with tissue spreaders and the like. Theapical puncture102 itself is initially formed using a small needle, and the puncture thereby formed is enlarged using a dilator. Purse string sutures or an access valve can be installed at the left ventricular apex so that the access ordelivery sheath100 may be advanced into the left ventricle without significant loss of blood.

FIG. 2B illustrates the procedure after expulsion of thepinch device20 from the access/delivery sheath100 into the ascending aorta, and/or retraction of thedistal end104 of the sheath into the left ventricle. The health care provider (e.g., doctor, surgeon, etc.) can maintain control of position of thepinch device20 during this retraction, e.g., by virtue of a plurality ofdeployment arms108 that engage thebuckles60. Thedeployment arms108 can be fixed or can be slidable within the access/delivery sheath100 and thus permit axial movement of thepinch device20. Furthermore, thedeployment arms108 can have sufficient stiffness to permit the health care provider (e.g., doctor, surgeon, etc.) to translate rotational movement of theaccess sheath100 to rotation of thepinch device20.

The illustratedpinch device20 has threebuckles60 and thus threedeployment arms108. Additional details of the control mechanism for deploying thepinch device20 will be described below. At this stage, thepinch device20 has fully self-expanded and is positioned above the aortic valve AV. Thearms108 can extend across a native valve at the commissures such that the arms and pinch device allow the native leaflets to continue functioning during deployment. For example, although not shown in the two-dimensional depiction, the threedeployment arms108 extend across the aortic valve AV at the commissures between the aortic valve leaflets AVL. In this way, thedeployment arms108 do not interfere with proper functioning of the leaflets, enabling the heart to continue to pump blood. Similar effect can be accomplished at the mitral valve using, for example, twoarms108 that connect to two buckles and cross at the two commissures of the mitral valve. Modifications for other valves are also possible.

Thebuckle60 andvertical finger62 can align with each of the peaks (e.g., the threepeaks30,32,34) of thepinch device20. Therefore, the peaks (e.g., the threepeaks30,32,34) can align with the native heart valve commissures, and the valleys (e.g., the threevalleys40,42,46) and any intermediate struts (e.g.,46,48) can align with the native valve leaflets (e.g., the three aortic valve leaflets AVL). Again, proper axial and rotational positioning of thepinch device20 can be accomplished by manipulation of thedeployment arms108 and/oraccess sheath100, and can be facilitated by radiopaque markers on thepinch device20 ordeployment arms108 that can be imaged from outside the body.

FIG. 2C shows thepinch device20 is moved from the location where it was expanded to a location closer to or in contact with the native valve (e.g., with the struts/peaks/valleys generally positioned outside or encircling the native leaflets). For example, in the example shown, thepinch device20 is retracted proximally until it is generally positioned at the aortic valve AV to the outside of the aortic valve leaflets AVL. Again, although it is not shown in two dimensions, the circumferential span of thepinch device20 between thepeaks30,32,34 (comprising thestruts46,48 and one of thevalleys40,42,44) lies to the outside of each of the three aortic valve leaflets AVL. Conversely, thepeaks30,32,34 as well as thevertical struts62 are aligned with the aortic valve commissures and pass between the aortic valve leaflets AVL. Thebuckles60 and terminal end of thedeployment arms108 can be located above or below the level of the native valve or aortic valve AV, depending on the precise positioning and length of thevertical struts62. Retraction of thepinch device20 may be accomplished by retracting thedeployment arms108 into theaccess sheath100, as shown, or simply by pulling back theaccess sheath100 in a proximal direction.

InFIG. 2D, adelivery catheter110 having aprosthetic heart valve112 mounted thereon has been advanced through theaccess sheath100 until the heart valve is expelled from thedistal end104. Theaccess sheath100 has an internal lumen (not shown) sufficiently large to enable passage of thedelivery catheter110 therethrough even in the presence of thedeployment arms108. Thedelivery catheter110 can be one used for delivering a variety ofexpandable heart valves112, such as for example the Edwards Certitude Delivery System from Edwards Lifesciences of Irvine, Calif. which is used to transapically deliver the SAPIEN 3 Transcatheter Heart Valve. The Certitude Delivery System is designed for use through lumens of access sheaths having an outer dimension of 18 Fr, which is equivalent to a diameter of 6 mm. Other delivery catheters and configurations are also possible as the access/delivery sheath100 can be configured to allow different types of delivery catheters to be introduced or passed therethrough.

FIG. 2E subsequently shows advancement of theprosthetic heart valve112 into a position within the native valve and pinch device and outward expansion of the prosthetic heart valve. For example,FIG. 2E shows advancement of theprosthetic heart valve112 into a position within the aortic valve leaflets AVL and outward expansion thereof. In the illustrated embodiment, aballoon114 on the distal end of theballoon catheter110 is used to plastically expand theheart valve112 outward into contact with the leaflets. Due to the surrounding presence of thepinch device20, the leaflets are clamped or pinched (e.g., partially or fully) therebetween. Typically, the expanded diameter of thepinch device20 is slightly smaller than the fully expanded diameter of theheart valve112. In this manner, full expansion of theheart valve112 causes slight outward expansion of thepinch device20, which sets up a reactive inward resilient spring force. Preferably, the diameters of the fully expandedheart valve112 and fully expandedpinch device20 are calibrated such that a predetermined clamping force is applied to the aortic valve leaflets AVL. For example, a clamping force of between about 1-3 pounds is considered desirable. This clamping force is sufficient to anchor theprosthetic heart valve112 into place, resisting subsequent migration. Other forms of expansion of theheart valve112 are also possible, such as self-expansion, mechanical expansion, or a combination of expansion forms.

In terms of positioning, theheart valve112 typically has three flexible leaflets (e.g., three artificial leaflets, leaflets formed of tissue such as pericardial tissue, etc.) therein divided by commissure regions. The three leaflets of theprosthetic valve112 are thus aligned with the three native aortic valve leaflets AVL and thus with the portions of thepinch device20 between thepeaks30,32,34. In a preferred embodiment, theheart valve112 is longer axially than the axial dimension of thepinch device20, at least between the peaks and valleys. The location of the distal end of theheart valve112 is approximately the same as thepeaks30,32,34 of thepinch device20, but theproximal end116 is preferably located farther into the left ventricle LV than thevalleys40,42,44.

In one embodiment, thedeployment arms108 remain attached to thebuckles60 until a desired position of theheart valve112 is established. For a balloon-expandable heart valve, once theballoon114 is inflated, the support frame of theheart valve112 expands outward into its final diameter, at which point thedeployment arms108 can be decoupled from thebuckles60. If theheart valve112 is self-expandable, the health care provider (e.g., doctor, surgeon, etc.) can be able to first expand and then constrict the valve for repositioning if necessary. Alternatively, thedeployment arms108 may be decoupled from thebuckles60 prior to introduction of theheart valve112, as seen inFIG. 2E. Again, radiopaque markers on thepinch device20 and theheart valve112 can be used to coordinate their dual deployment. It is important to note again that because of the single delivery system theheart valve112 is initially concentric with thepinch device20 such that just axial and rotational alignment is required.

FIG. 2E shows theheart valve112 fully expanded which pinches the aortic valve leaflets AVL against the inward spring force of thepinch device20. Because the cross-section is offset from the 120° spacing of the leaflets, this is not shown precisely in the drawing. During the process, the heart continues to beat and as soon as theheart valve112 is expanded and theballoon114 deflated, the prosthetic valve takes over the function of the native heart valve. Fluoroscopy can be used to confirm proper performance of theheart valve112. Finally, the health care provider (e.g., doctor, surgeon, etc.) can retract thedelivery catheter110 with the deflatedballoon114 back into theaccess sheath100. The entire delivery system is then removed from the body with the various puncture and access incisions closed up.

Additional Pinch Device Features and Configurations

Different numbers of peaks, valleys, struts, etc. can be used in a pinch device. For example,FIG. 3A is a perspective view of anexemplary pinch device120 having sixpeaks122 and sixvalleys124 around its circumference for use in heart valve replacement procedures described herein. As above, there are buckles each at an end of an extension. For example, threebuckles126 at the lower end of three vertical extensions128 (e.g., fingers or struts). Thebuckles126 are positioned below everyother peak122, and thus thepinch device120 is suitable for use at the aortic valve with thevertical struts128 and buckles126 extending along the commissures and between the leaflets thereof to allow function of the native leaflets during delivery and deployment. In between each of thepeaks122 having the integrated buckles126, additional struts (shown in a W-shaped strut configuration) are provided which can enhance the clamping force of thepinch device120 against the native leaflets.

The extensions and buckles can also be configured in different ways. For example,FIG. 3B is anexemplary pinch device130 modified for an alternative valve replacement procedure. The main portion of thepinch device130 is similar to thepinch device20 described above, with threepeaks132 evenly spaced between threevalleys134. However, instead of the buckles extending downward from thepeaks132, extensions orvertical struts136 havingbuckles138 on their ends extend upward from the threepeaks132. With this configuration, the delivery system engages thepinch device130 from above, meaning thepeaks132 are on the proximal end and thevalleys134 extend distally, in terms of delivery orientation. An exemplary procedure may involve advancing the delivery system through the vasculature and down the ascending aorta AA to deliver thepinch device130 around the aortic valve leaflets AVL. Alternatively, thepinch device130 may be advanced into a position around the mitral valve leaflets. It will be understood that a number of possible delivery routes and valve replacement procedures may be performed using thepinch device130.

Access/Delivery System

FIGS. 4A-4D are perspective views of an exemplary access ordelivery system150 having the tubular access ordelivery sheath100 described above showing sequential steps in expulsion and release of thepinch device20 from the sheath. Theaccess system150 includes theaccess sheath100 extending distally from aproximal handle152, and can include and/or house a linear displacement mechanism for thepinch device20 and/or sheath. For example, the displacement mechanism can be configured to move the sheath relative to the pinch device and handle (e.g., the pinch device and the handle or a portion of the handle can be fixed relative to each other, while the sheath moves), can be configured to move the pinch device relative to the sheath and handle (e.g., the sheath and handle or a portion of the handle can be fixed relative to each other, while the pinch device moves), a combination of these, etc. In the illustrated embodiment, thehandle152 includes aproximal grip portion154 slidably mounted over adistal housing156 in a telescoping fashion. Thegrip portion154 is fixed to move linearly with respect to thedeployment arms108 which in turn are coupled to the buckles60 (FIG. 2B) on thepinch device20. Thegrip portion154 is shown moving to the left betweenFIGS. 4A and 4B relative to thehousing156 which expels thepinch device20 from thedistal end104 of theaccess sheath100.

Linear motion of thegrip portion154 relative to thehousing156 may be accomplished in a variety of ways. In the illustrations, athumbwheel160 having gear teeth on its periphery is mounted for rotation on thegrip portion154 and has a lower generatrix in meshing engagement with arack162 having similar gear teeth axially positioned on thehousing156. A user can easily hold thegrip portion154 while manipulating thethumbwheel160 to expel thepinch device20 from thesheath100. Alternatively, thehandle152 may be formed of a single member incorporating a linear slider which may be moved back and forth to displace thepinch device20. Still further linear displacement mechanisms or other displacement mechanisms are contemplated.

FIGS. 4C and 4D, in conjunction withFIGS. 5A and 5B, show an exemplary configuration for coupling and decoupling thedeployment arms108 and thebuckles60 on thepinch device20, although other configurations are also possible. In the enlarged view ofFIG. 5A, adistal end164 of one of thedeployment arms108 extends within the central aperture of the opensquare buckle60. Thedeployment arms108 are tubular and thedistal end164 is separated from the main portion of the arm by acutout166 formed partly as a rampededge168 on its distal side. Afilament170 extends along the length of thetubular arm108, emerges at thecutout166, and passes over a proximal portion of thebuckle60 and through thedistal end164. Thefilament170 then continues in a distal direction along thevertical strut62 and can be tucked underneath thefabric24 that covers thepinch device20. Thefilament170 can be made of a polymer suture material, can be a thin Nitinol wire, or be made of another suitable material. By this arrangement, thebuckle60 is captured within thecutout166 at the distal end of thedeployment arm108.

FIG. 5B is an enlarged view of thedeployment arm108 decoupling from thebuckle60. In particular, thefilament170 is retracted proximally which releases thebuckle60 from within thecutout166. The rampededge168 facilitates the release by minimizing any friction.

Thefilament170 can be retracted in a variety of ways. For example,FIG. 4C illustrates an exemplary two-step operation for retracting thefilament170, which is also shown in greater detail inFIGS. 7A-7C. Namely, instep1 the user first rotates anend cap172 provided on a proximal end of thehandle152 which enables proximal movement of anend sleeve174 instep2. As will be described below with reference toFIG. 6E, thefilament170 is fixed linearly with respect to theend sleeve174 and moves relative to thedeployment arm108 with the end sleeve. Of course, all threefilaments170 are displaced in a proximal direction with theend sleeve174, which releases all threebuckles60 and decouples theaccess system150 from thepinch device20.

FIG. 4D illustrates subsequent proximal retraction of thedeployment arms108 within theaccess sheath100. This can be accomplished by reversing the direction of thethumbwheel160 on therack162 which can pull thegrip portion154 back along thehousing156. As mentioned above, this operation can be performed prior to or after advancement of the prosthetic heartvalve delivery catheter110.

FIG. 6A is a broken vertical sectional view through theexemplary access system150 including theaccess sheath100 with apinch device20 compressed and held therein.FIG. 6B is a vertical sectional view through a distal end of theaccess sheath100 after expulsion of thepinch device20 therefrom but before decoupling of thedeployment arms108.FIG. 6C is a sectional view through theproximal handle152 in particular showing a number of hemostatic seals, whileFIGS. 6D and 6E are enlarged views of portions ofFIG. 6C.

The access/delivery sheath100 can be inserted into a body and extend into the heart from the exterior of the body, with theproximal handle152 located outside the body. In one embodiment, theaccess sheath100 possesses an external hydrophilic coating and has a length of at least 8 inches (˜20 cm) so that it can extend from outside the body into the left ventricle and reach the native annulus or aortic annulus. However, for transapical procedures, theaccess sheath100 can have a maximum length of about 12 inches (˜30 cm) to avoid becoming unduly flexible.

Thehandle152 inFIG. 6A is in the same configuration as seen in solid line inFIG. 4A, with thegrip portion154 telescoped proximally away from thehousing156. Consequently, thedeployment arms108 andpinch device20 are retracted into theaccess sheath100. Once deployed, as seen inFIG. 6B, thedeployment arms108 can project forward from or relative to thedistal end104 of the sheath. The natural elasticity (or, optionally, pre-set shape, e.g. in shape memory material) of thepinch device20 can permit it to expand to an enlarged diameter. Because of the high flexibility of thedeployment arms108, they can flex outwardly by virtue of their engagement with thebuckles60.

It should be noted that when thepinch device20 is retracted within theaccess sheath100, a central channel remains through the pinch device even though it is compressed into a much smaller diameter. The central channel permits passage of a guide wire, such as that shown at106 inFIG. 2A, or other instruments used during the insertion procedure. It should also be noted that, when thepinch device20 is constricted into its smaller diameter within thesheath100, the V-shapedstruts46,48 can come together in linear alignment and extend, such that thevalleys40,42,44 are located proximal to thebuckles60. Conversely, when expanded, the struts (e.g., V-shapedstruts46,48) can spread apart and be shorter axially, and thebuckles60 can be located proximal thereto as shown inFIG. 6B.

Thehandle152 provides both a mechanism for displacing thepinch device20 axially as well as a number of seals for preventing blood leakage around instruments passed therethrough, including the heartvalve delivery catheter110. In this regard, theaccess system150 functions somewhat like an introducer used to establish an access pathway into the heart for passage of instruments. For example, as seen inFIG. 6C, acentral lumen180 can extend through the middle of thehandle152 from the proximal end of theaccess sheath100 to anaperture182 in theend cap172. Thecentral lumen180 in thehandle152 can be common with and extend into the lumen within theaccess sheath104 for passage of the delivery catheter110 (e.g., a balloon catheter, etc.). Within thehandle lumen180 can reside one or more valves, for example,hemostasis valves184,186,188, which can be mounted within an inner housing or funnel-shaped inner housing for sealing around different sized instruments. For example, looking in series from proximal to distal inFIG. 6C, thehandle152 encompasses across-slit valve184, adisk valve186, and a duck-bill valve188. These three valves function to provide a seal when there are no instruments, as well as when several different sizes of instruments pass through thehandle152. For example, the valves can seal around both theguidewire106 and thedelivery catheter110 as previously shown.

Additionally, the access/delivery system can include one or more seals between parts of thehandle152 that prevent leakage from within thecentral lumen180. Thehousing156 can be attached to a tapereddistal nose190 around the distal end of which can be provided an elastomericstress relief ferrule192. The proximal end of theaccess sheath100 can be fitted closely through a through bore in theferrule192 and can be secured within a lumen of thedistal nose190. As seen best inFIG. 6D, an O-ring194 can be used to provide a seal around the exterior of theaccess sheath100 and the interior of thedistal nose190. Furthermore, a tubularelastomeric seal196 can be used and can be configured such that it extend around a segment of theaccess sheath100 that spans the junction between thedistal nose190 andferrule192. Each of thedeployment arms108 can extend proximally into the handle from channels within theaccess sheath100 and can angle radially outward intochannels197 in thedistal nose190. In doing so, thedeployment arms108 pass outward through the wall of theaccess sheath100. To prevent blood leakage through these openings, thearms108 can pass through small apertures that can be formed in theelastomeric seal196, which apertures can be configured to close/seal around each of thedeployment arms108 and prevent leakage. At the same time, the apertures in theseal196 can be configured and formed such that they do not unduly inhibit sliding movement of thedeployment arms108 therethrough. A second O-ring198 can be used to further provide a seal around a distal end of the inner housing. In this way, blood that travels proximally through theaccess sheath100 is prevented from escaping radially outward through thecentral lumen180 within thehandle152.

FIG. 6E illustrates a proximal section of thehandle152 which is instructive in understanding the exemplary mechanism shown for decoupling thedeployment arms108 from thepinch device20. As mentioned above, thegrip portion154 slidably mounts over thedistal housing156 in a telescoping fashion. Aproximal end200 of eachdeployment arm108 is secured within a bore of anannular washer202 that is secured within thegrip portion154 such as with fasteners204 (seeFIG. 6C). Consequently, thedeployment arms108 are secured to and move axially with thegrip portion154. Theinner filaments170 that extend through thedeployment arms108 continue proximally through an aperture formed in the proximal end of thegrip portion154 and through another aperture provided in anannular wall206 which is part of theend sleeve174. Anenlargement208 such as a crimped tube, bead, or other such device is secured to a proximal end of thefilament170 to prevent the filament from being able to slide distally relative to theend sleeve174. Consequently, when theend sleeve174 is displaced in a proximal direction relative to thegrip portion154, such as was described above with reference toFIG. 4C, thefilament170 is also displaced in proximal direction relative to therespective deployment arm108.

FIGS. 7A-7C are enlarged views of the proximal end of the access system handle152 showing operation of the exemplary decoupling assembly for thedeployment arms108.FIG. 7A illustrates inward compression of a pair of spring-loadedlocking buttons210 to permit rotation of theend cap172. More specifically, the lockingbuttons210 can be configured to prevent rotation of theend cap172 until they are depressed. Other locking mechanisms to prevent undesired rotation are also possible. As described above, theend cap172 is rotated in a clockwise (CW) direction prior to displacing theend sleeve174 proximally relative to thegrip portion154.

FIG. 8 is a perspective view of showing theend cap172 removed from theend sleeve174. Theannular wall206 of theend sleeve174 can be seen as well as theenlargements208 on the proximal end of the filaments (not shown). A plurality of locking tabs212 (also seen inFIG. 6C) extend proximally from theannular washer202 secured to thegrip portion154 throughopenings214 provided in theannular wall206. Each of the lockingtabs212 can have a small radially inward tooth (not numbered) thereon that catches on theopenings214 and secures theend sleeve174 on the proximal end of thegrip portion154. Because the lockingtabs212 are cantilevered and flexible, they can be cammed outward in a variety of ways to release the teeth from theopenings214, thus releasing theend sleeve174 to move.

Rotation of theend cap172 can cam the lockingtabs212 outward. For example,FIG. 8 shows an exemplary trilobularcam member216 extending in a distal direction on the inside of theend cap172. When assembled to the end of theend sleeve174, thecam member216 fits radially between the three lockingtabs212, as seen inFIG. 9A. Prior to rotation of theend cap172 and displacement of theend sleeve174, lesser radial portions of thecam member216 are adjacent to or in contact with the lockingtabs212. Rotation of theend cap172 by 60° causes the lobes of the trilobularcam member216 to cam the lockingtabs212 outward, as seen inFIG. 9B. This releases the teeth on the lockingtabs212 from theopenings214 in theend sleeve174, thus allowing the user to pull the end sleeve in a proximal direction, as seen inFIG. 7C. Once again, this causes theannular wall206 to pull theenlargements208 on the ends of thefilaments170 proximally, thus decoupling thedeployment arms108 from thepinch device buckle60, as was seen inFIG. 5B.

While the invention has been described with reference to particular embodiments, it will be understood that various changes and additional variations may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention or the inventive concept thereof. In addition, many modifications may be made to adapt a particular situation or device to the teachings of the invention without departing from the essential scope thereof. Features and components described with respect to one embodiment can be incorporated into other embodiments even if not expressly described with respect to that embodiment. Methods can include any of the steps recited or implicitly included herein, and the steps can be ordered in different ways. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed herein, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims (11)

What is claimed is:

1. A prosthetic heart valve and delivery system, comprising:

an expandable prosthetic heart valve having a constricted diameter and an expanded diameter;

a delivery catheter having a distal end on which the heart valve is mounted;

a pinch device separate from the heart valve that has an expanded state defining an annular frame formed around a central axis and having peaks and valleys extending in opposite axial directions around its periphery, the pinch device including an inner body covered with a biocompatible fabric covering, with a plurality of buckles integrated with the inner body and projecting from a proximal end without being covered by the fabric covering, the pinch device in its expanded state being sized slightly smaller than the expanded diameter of the heart valve;

and an access system including a proximal handle and a distal access sheath, the handle and sheath defining a common lumen sized to allow passage therethrough of the distal end of the delivery catheter with the heart valve in its constricted diameter thereon, and the handle having one or more hemostatic seals to prevent blood leakage proximally past the distal end of the delivery catheter during use, the access system including a plurality of deployment arms, wherein at least one of the plurality of deployment arms and the sheath are axially movable relative to the other, wherein each of the plurality of deployment arms is coupled to one of the buckles of the pinch device, and wherein, prior to delivery, the pinch device is positioned in a constricted state within a distal end of the access sheath and is distal with respect to the distal end of the delivery catheter, such that the pinch device can be expelled from the access sheath and self-expand prior to expansion of the heart valve while connected to the plurality of deployment arms,

wherein the system is configured such that the distal access sheath can be introduced into the heart and advanced so that the distal end thereof is proximate a native heart valve, whereupon the pinch device can be expelled therefrom and positioned around native heart valve leaflets and the delivery catheter can be advanced to position the heart valve within the native heart valve leaflets such that expansion of the heart valve pinches the leaflets between the heart valve and pinch device,

wherein the proximal handle of the access system includes an advancement mechanism for axially displacing the deployment arms, and a release mechanism for decoupling each deployment arm from its corresponding buckle, and

wherein the release mechanism includes a filament extending from the proximal handle to a distal end of each deployment arm that nominally locks the deployment arm to the corresponding buckle, and an end sleeve on the proximal grip portion to which each filament is attached, wherein relative axial movement of the end sleeve with respect to the proximal grip portion pulls the filaments in a proximal direction.

2. A prosthetic heart valve system, comprising:

an expandable prosthetic heart valve having a constricted diameter and an expanded diameter; a delivery catheter having a distal end on which the heart valve is mounted; a pinch device separate from the heart valve that has an expanded state defining an annular frame formed around a central axis and having peaks and valleys extending in opposite axial directions around its periphery, the pinch device including an inner body, the pinch device in its expanded state being sized slightly smaller than the expanded diameter of the heart valve; and an access system including a proximal handle and a distal access sheath, the handle and sheath defining a common lumen sized for passage therethrough of the distal end of the delivery catheter with the heart valve in its constricted diameter thereon, the access system including a plurality of deployment arms each coupled to the pinch device, wherein at least one of the sheath and the plurality of deployment arms is axially movable relative to the other, wherein the pinch device is positioned, prior to delivery, in a constricted state within a distal end of the access sheath and distal with respect to the distal end of the delivery catheter, such that the pinch device can be expelled from the access sheath and self-expand prior to expansion of the heart valve, the proximal handle having an advancement mechanism for axially displacing the deployment arms in a distal direction and/or retracting the sheath, and a release mechanism for decoupling each deployment arm from the pinch device,

wherein the system is configured such that the distal access sheath can be introduced into the heart and advanced so that the distal end thereof is proximate a native heart valve, whereupon the pinch device can be expelled therefrom and positioned around native heart valve leaflets and the delivery catheter can be advanced to position the heart valve within the native heart valve leaflets such that expansion of the heart valve pinches the leaflets between the heart valve and pinch device, and

wherein the release mechanism includes a filament extending from the proximal handle to a distal end of each deployment arm that nominally locks the deployment arm to the corresponding buckle, and an end sleeve on the proximal grip portion to which each filament is attached, wherein relative axial movement of the end sleeve with respect to the proximal grip portion pulls the filaments in a proximal direction.

3. The system ofclaim 2, wherein the pinch device has a plurality of buckles integrated with the inner body and projecting from a proximal end without any fabric covering, and the buckles on the pinch device are located at terminal ends of three fingers extending in a proximal direction from the pinch device and distributed evenly around a periphery of the pinch device, and wherein the deployment arms are each coupled to one of the buckles of the pinch device.

4. The system ofclaim 3, wherein the peaks of the pinch device project in a distal direction and the valleys project in a proximal direction, and the fingers extend proximally from three of the peaks of the pinch device.

5. The system ofclaim 3, wherein the peaks of the pinch device project in a proximal direction and the valleys project in a distal direction, and the fingers extend from three of the peaks distributed evenly around a periphery of the pinch device.

6. The system ofclaim 2, wherein the inner body includes circumferential struts connecting each two adjacent peaks and valleys each of which is generally S-shaped, with two curvatures separated by a point of inflection.

7. The system ofclaim 6, wherein each of the circumferential struts terminates at its corresponding peak and valley in an asymptotic manner such that it is nearly aligned with the vertical Z-axis.

8. The system ofclaim 2, wherein the advancement mechanism comprises a thumb wheel mounted for rotation on the proximal grip portion that engages a gear rack fixed to the distal housing so as to advance the proximal grip portion.

9. The system ofclaim 2, wherein the end sleeve is prevented from relative axial movement prior to rotational movement with respect to the proximal grip portion.

10. The system ofclaim 9, further including a pair of opposed locking tabs on the end sleeve that prevent rotational movement with respect to the proximal grip portion prior to depressing both locking tabs radially inward.

11. The system ofclaim 2, wherein the proximal handle includes a distal housing and the advancement mechanism comprises a proximal grip portion slidably mounted over the distal housing in a telescoping fashion.

Images